{"id":{"repo_id":"must-thes","oai_identifier":"oai:scholarsmine.mst.edu:doctoral_dissertations-2004"},"canonical_url":"https://search.dev.ndltd.org/etd/must-thes/oai:scholarsmine.mst.edu:doctoral_dissertations-2004","repository":{"repo_id":"must-thes","name":"Missouri University of Science and Technology","base_url":"https://scholarsmine.mst.edu/do/oai/"},"display":{"title":"The low-temperature sintering behavior of (La,Ca)CrO₃","abstract":"<p>\"Calcium doped lanthanum chromite has suitable properties for use as a solid oxide fuel cell interconnect, but it is difficult to sinter. The purpose of this study was to develop methods of sintering this material in air at temperatures below 1500°C. The results are compiled into three papers.</p> <p>The first paper discusses the formation of pure and Ca doped lanthanum chromate (LaCrO<sub>4</sub>). This compound transforms to lanthanum chromite (LaCrO<sub>3</sub>) and calcium chromate (CaCrO<sub>4</sub>) between 600 and 700°C which subsequently form a solid solution, (La,Ca)CrO<sub>3</sub>. The surface segregation of Ca and phase separation of CaCrO<sub>4</sub> are discussed.</p> <p>The second paper addresses the sintering behavior of (La<sub>.6</sub>Ca<sub>.4</sub>)<sub>x</sub>CrO<sub>3</sub> where x is varied between 0.95 to 1.05. Densities of up to 93% of the theoretical were obtained by optimizing processing parameters. Compositions with x greater than or equal to unity showed the best sinterability.</p> <p>The solubility of CaCrO<sub>4</sub> in LaCrO<sub>3</sub> versus temperature was determined and is presented in the third paper. Powders which were heated slowly had a higher apparent solvus temperature than those which started as single phase solids and were heated quickly. The optimum composition for sintering was shown to contain between 25 and 30 mol% calcium\"--Abstract, page iii.</p>","abstract_html":"&lt;p&gt;&quot;Calcium doped lanthanum chromite has suitable properties for use as a solid oxide fuel cell interconnect, but it is difficult to sinter. The purpose of this study was to develop methods of sintering this material in air at temperatures below 1500°C. The results are compiled into three papers.&lt;/p&gt; &lt;p&gt;The first paper discusses the formation of pure and Ca doped lanthanum chromate (LaCrO&lt;sub&gt;4&lt;/sub&gt;). This compound transforms to lanthanum chromite (LaCrO&lt;sub&gt;3&lt;/sub&gt;) and calcium chromate (CaCrO&lt;sub&gt;4&lt;/sub&gt;) between 600 and 700°C which subsequently form a solid solution, (La,Ca)CrO&lt;sub&gt;3&lt;/sub&gt;. The surface segregation of Ca and phase separation of CaCrO&lt;sub&gt;4&lt;/sub&gt; are discussed.&lt;/p&gt; &lt;p&gt;The second paper addresses the sintering behavior of (La&lt;sub&gt;.6&lt;/sub&gt;Ca&lt;sub&gt;.4&lt;/sub&gt;)&lt;sub&gt;x&lt;/sub&gt;CrO&lt;sub&gt;3&lt;/sub&gt; where x is varied between 0.95 to 1.05. Densities of up to 93% of the theoretical were obtained by optimizing processing parameters. Compositions with x greater than or equal to unity showed the best sinterability.&lt;/p&gt; &lt;p&gt;The solubility of CaCrO&lt;sub&gt;4&lt;/sub&gt; in LaCrO&lt;sub&gt;3&lt;/sub&gt; versus temperature was determined and is presented in the third paper. Powders which were heated slowly had a higher apparent solvus temperature than those which started as single phase solids and were heated quickly. The optimum composition for sintering was shown to contain between 25 and 30 mol% calcium&quot;--Abstract, page iii.&lt;/p&gt;","abstract_has_math":false,"creators":["Carter, John David"],"institution":"University of Missouri--Rolla","degree_name":"Ph. D. in Ceramic Engineering","degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2016,"date_issued":"2016-02-10T08:00:00Z","date_published":"2016-02-10T08:00:00Z","updated_at":"2026-07-24T03:20:02Z","subjects":["Ceramic Materials"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://scholarsmine.mst.edu/doctoral_dissertations/1002","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Carter, John David"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.available","label":"Dc Date Available","values":["2016-02-10T08:00:00Z"]},{"key":"dc:type","label":"Dc Type","values":["Dissertation - Restricted Access"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph. D. in Ceramic Engineering"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Missouri--Rolla"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Ceramic Materials"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://scholarsmine.mst.edu/doctoral_dissertations/1002"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["<p>\"Calcium doped lanthanum chromite has suitable properties for use as a solid oxide fuel cell interconnect, but it is difficult to sinter. The purpose of this study was to develop methods of sintering this material in air at temperatures below 1500°C. The results are compiled into three papers.</p> <p>The first paper discusses the formation of pure and Ca doped lanthanum chromate (LaCrO<sub>4</sub>). This compound transforms to lanthanum chromite (LaCrO<sub>3</sub>) and calcium chromate (CaCrO<sub>4</sub>) between 600 and 700°C which subsequently form a solid solution, (La,Ca)CrO<sub>3</sub>. The surface segregation of Ca and phase separation of CaCrO<sub>4</sub> are discussed.</p> <p>The second paper addresses the sintering behavior of (La<sub>.6</sub>Ca<sub>.4</sub>)<sub>x</sub>CrO<sub>3</sub> where x is varied between 0.95 to 1.05. Densities of up to 93% of the theoretical were obtained by optimizing processing parameters. Compositions with x greater than or equal to unity showed the best sinterability.</p> <p>The solubility of CaCrO<sub>4</sub> in LaCrO<sub>3</sub> versus temperature was determined and is presented in the third paper. Powders which were heated slowly had a higher apparent solvus temperature than those which started as single phase solids and were heated quickly. The optimum composition for sintering was shown to contain between 25 and 30 mol% calcium\"--Abstract, page iii.</p>"]},{"key":"dc:title","label":"Title","values":["The low-temperature sintering behavior of (La,Ca)CrO₃"]}]}],"canonical_facts":{"dc:creator":["Carter, John David"],"dc:date.available":["2016-02-10T08:00:00Z"],"dc:description.abstract":["<p>\"Calcium doped lanthanum chromite has suitable properties for use as a solid oxide fuel cell interconnect, but it is difficult to sinter. The purpose of this study was to develop methods of sintering this material in air at temperatures below 1500°C. The results are compiled into three papers.</p> <p>The first paper discusses the formation of pure and Ca doped lanthanum chromate (LaCrO<sub>4</sub>). This compound transforms to lanthanum chromite (LaCrO<sub>3</sub>) and calcium chromate (CaCrO<sub>4</sub>) between 600 and 700°C which subsequently form a solid solution, (La,Ca)CrO<sub>3</sub>. The surface segregation of Ca and phase separation of CaCrO<sub>4</sub> are discussed.</p> <p>The second paper addresses the sintering behavior of (La<sub>.6</sub>Ca<sub>.4</sub>)<sub>x</sub>CrO<sub>3</sub> where x is varied between 0.95 to 1.05. Densities of up to 93% of the theoretical were obtained by optimizing processing parameters. Compositions with x greater than or equal to unity showed the best sinterability.</p> <p>The solubility of CaCrO<sub>4</sub> in LaCrO<sub>3</sub> versus temperature was determined and is presented in the third paper. Powders which were heated slowly had a higher apparent solvus temperature than those which started as single phase solids and were heated quickly. The optimum composition for sintering was shown to contain between 25 and 30 mol% calcium\"--Abstract, page iii.</p>"],"dc:identifier":["https://scholarsmine.mst.edu/doctoral_dissertations/1002"],"dc:subject":["Ceramic Materials"],"dc:title":["The low-temperature sintering behavior of (La,Ca)CrO₃"],"dc:type":["Dissertation - Restricted Access"],"thesis:degree_name":["Ph. D. in Ceramic Engineering"],"thesis:institution_name":["University of Missouri--Rolla"]},"updated_at":"2026-07-24T03:20:02Z"}